Narrabeen Beach, located Sydney, Australia, has undergone frequent storm wave events. The beach form has an adaptive ability to evolve from storm profile to berm profile with little human intervention. In order to investigate the self-recovery capability of the headland bay after storm waves, this paper analyzes how beach evolves during the post-storm calm weathers and identify the main hydrodynamic factors that dominate the beach recovery based on the multi-year continuous measurement data of Narrabeen Beach. The results show that there are spatial differences along the shore in the recovery rates, with the fastest recovery rate in the middle of the beach. Besides, southeast breezes with small wave-height and long wave-period contribute most to the storm-profiles’ recovery, especially to the northern-to-central portion. Whilst for the southern part of the headland bay tidal force modulate the beach recovery efficiency more. Accordingly, a concept of cumulative wave energy considering tidal range is proposed by this study and found to well correlated with the self-recovery ability of the southern beach profile. Through investigation, variation of wave directions induced by topography, along with geological and geomorphological features all play a vital role on the spatial inhomogeneity of the recovery efficiency for the headland bay. In addition, from the secular time scale, the recovery ability of the storm profiles is also controlled by the Southern Oscillation Index. The analysis and findings of this paper can provide useful references for disaster prevention and mitigation, and post-disaster protection and restoration for a headland bay under extreme sea forces.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |